Valves and mixing devices for combining two different liquids in a specific proportion have long been known in the prior art. Thus, it is frequently desirable to add some type of liquid concentrate to water or other liquid to provide a mixture or solution having specific properties and proportions.
Examples of prior art liquid mixing devices include U.S. Pat. Nos. 3,791,410; 4,469,137; 4,285,367; 4,761,077 and 4,549,813.
U.S. Pat. No. 3,791,410 discloses a liquid mixing device in which an outer container has an inlet for introducing a first liquid under pressure and an inner container integrally formed therewith and having an inlet in a common wall for admitting a second liquid to become mixed with the first liquid. A regulatable valve is provided for regulating the amount of second liquid introduced to the first liquid.
U.S. Pat. No. 4,469,137 is directed to a liquid metering and mixing aspirator for mixing liquid soft drink concentrate with water. It includes an elongate aspirator chamber which communicates with a water supply passage on the one hand and with a concentrate metering valve on the other hand. The two liquids are transmitted from the aspirator chamber to a mixing tube which includes a water jet deflecting means.
U.S. Pat. No. 4,285,367 is directed to a mixing device to effect an intense and rapid mixing of two fluids which is comprised of a venturi tube connected to the first fluid inlet and a feed member disposed around the venturi tube through which the second fluid can flow.
U.S. Pat. No. 4,761,077 is directed to a mixing apparatus including a cylindrical mixing chamber having a fluid inlet at one end, a frustoconical tubular end piece connected to the other end and flaring outwardly by progressively increasing in diameter in an outward direction to form a fluid outlet. The mixing chamber has a plurality of row of openings inclined inwardly toward the fluid outlet. An outer jacket surrounds the liquid mixing chamber to form a liquid receiving chamber.
U.S. Pat. No. 4,549,813 is directed to a mixing apparatus for a plurality of liquids and includes an elongated passage for carrying one of the liquids to a mixing chamber. A check valve is positioned in the passage. A second liquid is introduced into the mixing compartment by way of an inlet chamber which establishes an annular flow in a direction normal to the flow of the laterally exiting streams.